Automatic gun mechanism



April 1944- H. o. EIANE 2, 45,7

' AUTOMATIC GUN MECHANISM Filed April 17. 1942 INVENTOR.

BY Wm fl 5W ATTORNEY.

Patented Apr. 4, 1944 UNHTED STATES errant ()FFICE.

3 Claims.

My invention relate to improvements in an automatic gun mechanism and particularly to my earlier invention of an Automatic rifle, illustrated and described in Patent No. 2,144,241, of Jan. 1'7, 1939, in which action rods operate in special longitudinal passages in the receiver, and are joined at their rear ends to a crosshead sleeve which carry means for operation of the breech bolt mechanism, and at their front ends to a crosshead on the piston rod which connects with the automatic source of power.

The main object of the present improvements is to strengthen the rear connections of the ac tion rods to the crosshead sleeve without any widening to the mechanism; a further object is to extend rearwardly the bearing supports for the action rods, by means of eccentric counterborings; a still further object is to eliminate features which tend to produce crystallization in operating parts after prolonged use.

I attain these objects by means of added features hereinafter more fully described and claimed having reference to the accompanying drawing in which Fig. 1 represents an elevational rear view of a receiver.

Fig. 2 is an elevational rear view of a crosshead sleeve.

Fig. 3 is a fragmentary top view of a crosshead junction between a piston rod and a pair of action rods, partly sectional.

Fig. 4 is a fragmentary side view of a rear portion of a left side action rod.

Fig. 5 is a fragmentary side view of a rear portion of a right side action rod.

A, in Fig. 1 is the receiver. 2 is the bore in the receiver. 3 and 3 are the longitudinal passages extending full length through the receiver, with eccentric counterborings 4 and 4 at their rear ends.

Referring to Fig. 1, it will be noted that the walls of the longitudinal passages 3 and 3, and the walls of the eccentric counterborings 4 and 4 coincide at the outer and lower points intersected by the dotted lines 5 and 5, which run through the diametrical center of the passages 3 and 3 and converge at the diametrical center of the bore 2 in the receiver A.

Fig. 2 shows a similar offset arrangement as in Fig. 1, here the dotted lines 5 and 5 pass through the diametrical center of two internally threaded eye-lugs 5 and l which are integrally formed on the crosshead sleeve 8 and likewise pass through the diametrical center of two circular dotted lines 3 and 3 which indicate position of the two longitudinal passages 3 and 3 with respect to the crosshead sleeve 8 when in its operative position. Fig. 4 shows a rear section of a left side action rod 9, which is provided with an integrally formed turning leaf l0, and an offset interruptedly threaded rear terminal II which carry a guide extension l2 and which turnably fits a reduced opening I3 in the rear end of the eyelug 6, for the purpose to bring the offset terminal I i in alignment to engage internally interrupted threads in the eye-lug 6 designated as H-A; (Internal threads in eye-lug i not shown.)

The terminal II will have at least 50 per cent more metal at the bottom of its thread than the normal diameter of the rod 9, so as to eliminate undue strain and crystallization of said terminal at the point of junction with the crosshead sleeve 8.

A gradual tapering down to normal diameter of the rod 9 at 14 serves as an anti-crystallization measure whereby the operative life of the rod is greatly lengthened.

The action rod I5 is similar to the rod 9 in its middle section, but different at both the rear and front terminals, being provided with full threads both at rear and front terminals. The rear terminal IS on the action rod I5 is provided with right hand threads, while the front terminal is left hand threaded; and the rod 9 is left hand threaded at both rear and front terminals.

The right side action rod [5 is provided With a shoulder H which bear against the front face of the eye-lug l and gradually tapers down for ward to the normal diameter of the rod l5.

Referring to Fig. 3, it will be noted that the forward ends of the action rods 9 and I5 are threaded into the crosshead lugs 18 and I9, located at the rear end of the piston rod 20 in such way that the rear portions of the lugs are drilled and reamed out to receive an unthreaded portion of each rod corresponding in depth to at least one and a half diameters of the rods.

The crosshead lugs l8 and I9 are thus made to serve as protecting sleeves over a suflicient portion of the rods 9 and I5 behind their terminal threads 2| and 22 so as to eliminate crystallization of the rods at the points where threading ends.

The front threads of the rod 9 and the thread on the inside of the crosshead lug l 8 are cut away in quarter sections at opposite sides, so that one quarter turn of the rod 9 will simultaneously engage or disengage the threads at H and 2| with threads in their respective lugs 6 and I8.

Referring again to Fig. 1, it will be clearly understood that the coinciding Walls of the longitudinal passages 3 and 3, and the eccentric counterborings 4 and 4 extend the bearing support for the rods 9 and IE to the rearward limits of the eccentric counterborings 4 and 4.

The designating numerals in this application are not the same as for corresponding parts in the aforementioned patent, but the difierent parts shown and described in this application are so nearly similar in appearance that their place and functioning can readily be understood.

I do not intend to limit my invention to the exact description and drawing as herein giVen, as many changes can be made without departing from the principle involved.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. In an automatic bolt-action rifle comprising a receiver formed with a central longitudinal bore and a pair of longitudinally disposed passages therethrough, the combination therein of a pair of eccentric counterborings formed at the rear end of said passages, a rearward extension of bearing surfaces in said passages by means of coincidence of internal walls between said passages and said eccentric counterborings, a pair of action rods provided with ofiset rear terminals complementarily formed for operative occupation of said passages and said eccentric counterborings, a rearward extension of bearing supports for said action rods through said eccentric counterborings, and means for securing a crosshead-sleeve to said rear terminals.

2. In an automatic bolt-action rifle comprising a receiver formed with a longitudinal central bore and a pair of longitudinally disposed passages in parallel spaced relation thereto, a pair of ccentric counterborings formed at the rear end of said passages, a rearward extension of bearing surfaces in said passages by means of coincidence of internal walls between said passage and said eccentric counterborings, a right side and a left side action rod operatively mounted in said passages, said right side rod provided with a rear terminal comprising an offset threaded section of enlarged diameter, a shoulder concentrically formed with respect to said threaded section, and a gradual tapering off from said shoulder to the normal diametrical size of said rod, said left side rod provided with a rear terminal comprising an offset interrupted thread section, an integrally formed turning leaf on said r-od, a reduced rearwardly extending guide-section, and a gradual tapering off from said turning leaf to the normal diametrical size of said rod, and a crosshead-sleeve provided with a pair of eye-1ugs complementarily formed for receiving said threaded sections on said rear terminals.

3. In an automatic bolt-action rifle comprising a receiver formed with a central longitudinally disposed bore and a pair of longitudinal passages therethrough, the combination therein of a pair of eccentric counterborings formed at the rear end of said passages, a rearward extension of bearing surfaces in said passages by means of coincidence of internal walls between said passages and said eccentric counterborings, a right side and a left side action rod provided with oil"- set threaded rear terminals for operative mounting in said passages, a crosshead-sleeve provided with a pair of eye-lugs for receiving said threaded rear terminals, and crosshead connections of said rods at their front ends comprising a threaded terminal at the front end of said right side rod. an interrupted thread terminal at the front end of said left side rod, a pair of complementarily formed lugs on said crosshead for receiving said threaded front terminals, and means formed on said crosshead lugs for protective covering of said rods to a suitable distance beyond the threaded limits of their front terminals.

- HALVOR OLSEN EIANE. 

